Accounting for non-monotonicity of quality as a function of quantization in quality and rate control for digital audio
First Claim
1. A computer-readable storage medium having stored thereon computer-executable instructions for causing a computer programmed thereby to perform a method comprising:
- selecting a quantization level within a range of quantization levels, wherein the selecting accounts for non-monotonicity of quality measure as a function of quantization level within the range, wherein the selecting comprises;
if the function is non-monotonic, selecting the quantization level in a first mode; and
otherwise, selecting the quantization level in a mode other than the first mode; and
quantizing audio information by the quantization level.
1 Assignment
0 Petitions
Accused Products
Abstract
An audio encoder regulates quality and bitrate with a control strategy. The strategy includes several features. For example, an encoder selects a quantization level within a range of quantization levels, where the selecting accounts for non-monotonicity of quality measure as a function of quantization level within the range. The encoder then quantizes audio information by the quantization level. Or, an encoder determines first and second quality measures associated with a first and second quantization levels, respectively, then determines a third quantization level within a quantization level range based upon location of a target quality on a trajectory of quality measure as a function of quantization level. The first and second quantization levels define endpoints of the quantization level range, and the first and second quality measures define endpoints of the trajectory. The function relates logarithm of quality measure in proportion to inverse logarithm of quantization level.
-
Citations
20 Claims
-
1. A computer-readable storage medium having stored thereon computer-executable instructions for causing a computer programmed thereby to perform a method comprising:
-
selecting a quantization level within a range of quantization levels, wherein the selecting accounts for non-monotonicity of quality measure as a function of quantization level within the range, wherein the selecting comprises; if the function is non-monotonic, selecting the quantization level in a first mode; and otherwise, selecting the quantization level in a mode other than the first mode; and quantizing audio information by the quantization level. - View Dependent Claims (2, 3, 4, 5)
-
-
6. A computer-readable storage medium having stored thereon computer-executable instructions for causing a computer programmed thereby to perform a method comprising:
-
selecting a quantization level within a range of quantization levels, wherein the selecting accounts for non-monotonicity of quality measure as a function of quantization level within the range, including; computing a first quality measure indicating quality of audio information as quantized by the quantization level; and recording the quantization level and the first quality measure in a trajectory point array; and quantizing the audio information by the quantization level. - View Dependent Claims (7, 8)
-
-
9. A computer-readable storage medium having stored thereon computer-executable instructions for causing a computer programmed thereby to perform a method comprising:
-
quantizing audio information by a quantization level; computing a first quality measure indicating quality of the audio information as quantized by the quantization level; comparing the first quality measure to a second quality measure for the audio information, the second quality measure indicating quality of the audio information as quantized by a previous quantization level; if the comparing indicates non-monotonicity of quality measure as a function of quantization level, designating the quantization level as inferior; and recording the quantization level and the first quality measure in a trajectory point array. - View Dependent Claims (10, 11)
-
-
12. In an audio encoder, a computer-implemented method comprising:
-
receiving audio information; quantizing and entropy coding the audio information, including; determining a first quality measure associated with a first quantization level; determining a second quality measure associated with a second quantization level; determining a third quantization level within a quantization level range based upon location of a target quality on a trajectory of quality measure as a function of quantization level, wherein the first and second quantization levels define endpoints of the quantization level range, wherein the first and second quality measures define endpoints of the trajectory, and wherein the function relates logarithm of quality measure in proportion to inverse logarithm of quantization level; and outputting the entropy coded, quantized audio information. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19, 20)
-
Specification